Hereditary hemorrhagic telangiectasia (HHT) is an inherited vasculopathy that results in dysregulated angiogenesis leading to the development of mucocutaneous telangiectasias and visceral organ arteriovenous malformations. HHT is the second most common inherited bleeding disorder. Recurrent, spontaneous epistaxis occurs in over 90% of affected individuals and is the hallmark of this disorder. Epistaxis and gastrointestinal bleeding result in the development of iron deficiency anemia in nearly half of all affected individuals. Considerable advances have been made in the understanding of the pathobiology, manifestations, and treatment of HHT in the last decade. International consensus treatment guidelines have been developed. Medical therapeutics have become the primary approach for treating HHT-related bleeding. The initial clinical studies evaluating medications for the treatment of HHT have involved repurposing drugs that were previously approved for other indications. In the wake of these efforts, several therapies specifically for HHT are currently being developed and are in preclinical studies and early phase human trials or may soon start pivotal phase III trials. The landscape of HHT is changing fast with increased awareness and diagnosis and the development of new and novel therapies, all of which will decrease morbidity and improve the quality of life of affected individuals.

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